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81.
Reactive oxygen species mediates a metabolic memory of high glucose stress signaling in bovine retinal pericytes 下载免费PDF全文
AIM: To investigate the role of reactive oxygen species (ROS) and antioxidant mechanism underlying the metabolic memory of bovine retinal pericytes (BRPs) induced by high glucose.
METHODS: Effects of high glucose levels and culture time on BRPs viability were evaluated by CCK-8. BRPs were grown in high-glucose media (30 mmol/L) for 4d followed by culture in normal glucose condition (5.6 mmol/L) for 4d in an experimental group. In contrast, in negative and positive control groups, BRPs were grown in either normal-glucose media or high-glucose media for 8d, respectively. The ROS levels, apoptosis, the expression and activity of manganese superoxide dismutase (MnSOD) in BRPs, as well as the protective effect of adeno-associated viral (AAV)-mediated over expression of MnSOD were determined separately by DCHFA, ELISA and Western blot.
RESULTS: Comparing the result of cells apoptosis, activity and protein expression of MnSOD and caspase-3, the cell culture system that exposed in sequence in 30 mmol/L and normal glucose for 4d was demonstrated as a suitable model of metabolic memory. Furthermore, delivery of antioxidant gene MnSOD can decrease BRPs apoptosis, reduce activated caspase-3, and reverse hyperglycemic memory by reducing the ROS of mitochondria.
CONCLUSION: Increased ROS levels and decreased MnSOD levels may play important roles in pericyte loss of diabetic retinopathy. BRPs cultured in high glucose for 4d followed by normal glucose for 4d could be an appropriate model of metabolic memory. rAAV-MnSOD gene therapy provides a promising strategy to inhibit this blinding disease. 相似文献
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Diabetic retinopathy (DR) is one of the leading causes of vision loss and can be effectively avoided by screening, early diagnosis and treatment. In order to increase the universality and efficiency of DR screening, many efforts have been invested in developing intelligent screening, and there have been great advances. In this paper, we survey DR screening from four perspectives: 1) public color fundus image datasets of DR; 2) DR classification and related lesion-extraction approaches; 3) existing computer-aided systems for DR screening; and 4) existing issues, challenges, and research trends. Our goal is to provide insights for future research directions on DR intelligent screening. 相似文献
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目的通过舒洛地特联合替米沙坦对2型糖尿病视网膜病变(diabeticretinopathy,DR)减少眼底微动脉瘤、延缓DR进展速度有效性的观察,评价舒洛地特和替米沙坦联合应用对DR的疗效。方法162例DR患者随机分为三组,替米沙坦组、舒洛地特组和联合治疗组,所有患者随访6个月,随访过程中定期检查眼底,空腹血糖、糖化血红蛋白、谷丙转氨酶、谷草转氨酶、纤维蛋白原。结果三组患者眼底微动脉瘤治疗后较治疗前均明显较少,差异有统计学意义(P〈0.05),治疗后三组间患者眼底微动脉瘤比较,差异无统计学意义(P〉0.05),联合治疗组与替米沙坦组、舒洛地特组相比,可延缓DR增殖型进展速度,差异有统计学意义(P〈0.05)。结论舒洛地特联合替米沙坦治疗DR能有效减少眼底微动脉瘤、延缓DR进展速度,疗效优于单一治疗组。 相似文献
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《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(6):397-401
We aimed to determine the prevalence and risk factors of retinopathy in hypertensive outpatients. Demographic data, accompanying diseases, anthropometric measurements, and blood and urine biochemistry of 655 hypertensive patients were evaluated. Hypertensive retinopathy rate was 66.3% (grade 1, 33.6%; grade 2, 32.7%). Age, duration of hypertension, and systolic blood pressure levels were significant risk factors for retinopathy (P = .048, P = .035, and P = .012, respectively). Any correlations between retinopathy and gender, body mass index, biochemistry, and associated diseases were not found. This study shows that the degree and duration of hypertension increases the incidence of retinopathy. Low-grade retinopathy seems not to be associated with other cardiovascular risks. 相似文献
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早产儿视网膜病变(ROP)是一种属于可避免、可控的儿童主要致盲性及低视力眼病。筛查是早检出、早干预和早治疗的前提和关键措施,对降低儿童致盲率及视力损伤具有重要意义。本文主要对我国ROP筛查和发病现状作一综述,以期为ROP的防治提供参考。 相似文献
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目的 分析表格式管理集束化护理在糖尿病视网膜病变(DR)术后患者中的应用价值。方法 回顾性分析2019年3月至2021年6月济南市第二人民医院收治的89例DR患者的临床资料,使用电脑进行随机编号,单数者为对照组44例(患眼59只),双数者为观察组45例(患眼65只)。对照组男21例,女23例,年龄(42.18±10.27)岁;观察组男23例,女22例,年龄(42.39±10.52)岁。对照组予以DR术后常规护理,观察组在对照组基础上予以表格式管理集束化护理干预,两组患者均干预1个月。干预前后使用自我护理能力测定量表(ESCA)和视功能损害眼病患者生存质量问卷(SQOL-DVI)评定患者的自护能力和生活质量;使用简易疾病感知问卷(BIPQ)评定两组患者疾病认知情况;比较两组患者术后并发症(角膜水肿、视网膜脱离和玻璃体出血)的发生情况。计量资料采用t检验,计数资料采用χ2检验,等级资料采用Mann-Whitney U检验。结果 干预后,观察组患者ESCA总分高于对照组[(110.19±13.59)分比(96.59±12.47)分],差异有统计学意义(t=4.916,P<0.001);BIPQ等级改善程度优于对照组(U=2.520,P=0.012);观察组并发症总发生率低于对照组[4.44%(2/45)比18.18%(8/44)],差异有统计学意义(χ2=4.210,P=0.040);干预后,观察组SQOL-DVI总分高于对照组[(87.59±12.64)分比(75.52±11.77)分],差异有统计学意义(t=4.660,P<0.001)。结论 表格式管理集束化护理可以提高DR术后患者的疾病自护能力和疾病认知水平,降低患者并发症的发生率,提高患者的生存质量。 相似文献
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